Modern processors produce a lot of heat and it requires large heatsinks with fans to keep everything running to specification. Thermal paste is one of the most critical components for keeping your processor cool, especially for those of us who overclock. The surfaces of processors and heatsink bases may appear to be completely flat to the naked eye but on a microscopic level there are many imperfections. These imperfections create air pockets between the cooler and the CPU which can have a great effect on thermal performance. This reduces the size of the contact area and air is a poor heat conductor.



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